Charlize Theron hit up Las Vegas this week to promote her upcoming adventure epicMad Max: Fury Roadat CinemaCon, but the star couldn't help showing how smitten she is for her boyfriend, Sean Penn.

"I'm in a great relationship," Charlize told ET's Brooke Anderson on Tuesday at the Las Vegas convention. "I'm really happy."

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While the Oscar-winning star said that things were going well, she also admitted that relationships that develop in the public eye can often feel a little awkward.

"You know, that stuff comes out and you always feel a little silly because it's your private life," Charlize said, adding, "[But] my life is in a really good place right now. And I'm just really happy for that."

The star couple was first spotted together in December 2013, but have remained relatively tight-lipped about their relationship with the press.

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At CinemaCon, the Dark Places actress also opened up about her son Jackson, who Charlize adopted in 2012.

When asked how motherhood has changed her approach to working and acting, she explained, "It's [about] finding balance."

"It's trying to have the life that you really want, and to feel like you're your own individual," Charlize, 39, continued. "And then also to, you know, be a mom and be there for your kid… I'm just trying to find that balance."

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Mad Max: Fury Road -- for which the Charlize had to go totally bald -- is headed to theaters May 15. Check out the insane trailer below for a look at her shocking transformation.

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